This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 13 |
| 3 | 44 |
| 4 | 162 |
| 5 | 637 |
| 6 | 2622 |
| 7 | 11188 |
| 8 | 49293 |
| 9 | 223768 |
| 10 | 1044661 |
| 11 | 5006126 |
| 12 | 24580704 |
| 13 | 123464593 |
| 14 | 633467893 |
| 15 | 3315948760 |
| 16 | 17690431736 |
| 17 | 96101620364 |
| 18 | 531196784996 |
| 19 | 2985589206506 |
| 20 | 17053375055317 |
| 21 | 98942675518256 |
| 22 | 582858713958087 |